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Updated: Oct 21, 2025

Modeling the Size Spectrum for Macroinvertebrates and Fishes in Stream Ecosystems
Published on: July 30, 2019
Abstract:
The abundance of bottom fauna and of fauna in drift was studied in streams treated with DDT at various times in the past. Recovery of the bottom fauna was found to be rapid, but that of drift was delayed. The relationship of quantity of drift to the increasing bottom standing crop during recovery from spray effects was found to be curvilinear. This suggested that drift is a density-related process. Possible mechanisms to explain drift are discussed, and the conclusions of earlier reports on recovery of streams following insecticidal treatment are questioned.
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